Rigorous modeling of lateral leakage loss in SOI thin-ridge waveguides and couplers

The transverse-magnetic to transverse-electric (TM-TE) mode coupling properties and the lateral leakage loss behavior of the propagating TM-like mode in silicon-on-insulator thin-ridge waveguides and directional couplers are investigated. Accurate calculation of the lateral leakage is performed by a mode matching technique in which the calculation window is left fully open in the lateral direction.